42 Comments

Thanks for the shout out regarding some of the issues caused in research methodology regarding definition of ‘intensity’ – I’d love it if we could all drop the term altogether for the sake of clarity to avoid misinterpretation by those making incorrect assumptions about what it means. Better definition leads to greater understanding of how to control for factors in research designs also. (Spoiler: we are working on some research at the moment attempting to examine a practically usable operational definition of ‘intensity’ of effort categories for use in research considering what has been looked at more recently in terms of differentiating the feelings of ‘discomfort’ associated with RT and the perception of ‘effort’ – preparing to empirically test our idea’s over the next year hopefully so I won’t reveal too much yet for fear of providing misleading recommendations that potentially end up unsupported).

Obviously this makes the acronym H ‘I’ T redundant (I’ve never particular been enamored with it anyway) and someone suggested to me once instead to use ‘WTF’ (Weight Training to Failure). I’m not sure an acronym is necessary expect in marketing and publicity respects and personally I don’t make a living selling the idea so it doesn’t matter to me. But I guess it would be amusing to see the acronym WTF in a peer reviewed article!!

I have to be honest that I love the openly encouraged debate in this area and often find that my own previous beliefs are being constantly tested which is exactly what science is about.

It always fascinates me that the interpretations of studies differ between readers. Brad argues the study isn’t representative of typical ‘HIT’ programs (and thus draws conclusions regarding the potential for a volume threshold) but I would argue it actually is more typical of the recommendations of many ‘HIT’ proponents. Although there are some who fall to one very extreme end of the spectrum recommending utilizing single exercises per muscle group using one set (From 1-3x/week). I am actually in favor of multiple exercises per muscle group (as are many other ‘HIT’ proponents) due to potential non-uniform muscle growth resulting from different exercise bio-mechanics. So my typical recommendations now revolve around 2 to 3 exercises per muscle group (whether different compound movements or a combination of compound and isolation – particularly for certain area’s in terms of prehab i.e. the lumbar extensors). I only recommend very abbreviated routines using single compound exercises for those who are mainly interested in the most bang-for-buck return in terms of health and fitness outcomes.

I’m a huge proponent of an ARPE approach also and recommend beginning from the group mean’s (where we can be reasonably sure that ~68% of the population receiving the recommendations will fall optimally) and then self-experimenting from there.

In general it’s actually quite surprising that alot of overlap in recommendations actually occurs, but it depends on where along the spectrum between ‘camps’ (ugh I hate that) those recommendations come from.

Thanks James! I appreciate the comment. Great to hear your thoughts and perspective. Love the WTF acronym, and the different take on “typical” routines just illustrates the lack of consensus in S&C with varying methodologies. It’s hard to pin things down when they’re such variation in each camp. Cheers, Bret

Thanks for your insightful feedback James. While I agree that multiple exercises are beneficial for maximizing hypertrophy, this was not an issue in the recent study by Baker et al. That study did not assess hypertrophy. Body comp was measured by skinfold, which has low accuracy in assessing regionally specific changes in FFM. Moreover, the results of the skinfolds seem highly suspect given greater skinfold reductions with less exercise — I’d question the validity (no ICC reported, which would have helped to provide credibility). Thus, the primary outcome measure here was strength as assessed by a single exercise for 1RM. The 1-set subjects therefore actually performed 3 sets per workout (9 sets per week) and one can assume that the culmination of the exercise enhanced strength in the tested exercise for a given muscle group (yes, there are regional differences of muscle activity between exercises, but there is a good amount of overlap as well).

As discussed in the podcast, the real issue which needs to be investigated is that of a volume threshold (i.e. at what point does additional volume become superfluous). There is compelling evidence that we need more than a single set to optimize the hypertrophic response as found in the meta-analyses by Krieger. The principle of individual differences tells us that the actual threshold will vary between individuals (as you alluded to in your comments). This is an area that I will be researching in the coming months.

I’ve not had a chance to hear the discussion yet, but I can’t wait! In the meantime I wanted to comment on Krieger’s meta-analysis regarding hypertrophy (2010) for which you provide the pdf. I published a critique of this meta-analysis, which I emailed to James Krieger (http://www.asep.org/asep/asep/JEPonlineDECEMBER2012_Fisher2.pdf), to which he has yet to post any response that I’m aware of.

In fact I’m intrigued as to why it hasn’t been added to the list of links since you (Bret) and Chris Beardsley discussed it in your Strength and Conditioning Research Magazine (January 2013). In fact, you misquoted it stating that I had missed 4 meta analysis, which – in discussion with Chris, it was admitted that a mistake had been made on your (pl, not individual) fault (the meta analysis made reference to were regarding strength not hypertrophy) and I was invited to write a piece for your magazine in which you (again; pl) would amend your previous error.

The point to this comment is not to rant, but to highlight that Krieger does a great job by performing a meta-analysis, but actually a poor job in doing so. His studies do not meet his criteria, he fails to mention methods of measuring hypertrophy ranging from tape measure circumference to MRI, supplements used within at least one of the studies, and differing ages and training status’. All of which make providing any single recommendation a little unreliable and more; unscientific.

Of course; you might discuss all of this in your podcast, in which case I’ll likely withdraw this comment. But until then I thought this was worth mentioning.

James, I knew I was missing something! I added in your link. Sorry about that.

Feel free to post your thoughts/beliefs pertaining to this topic – this is a blog, not a journal. We have more freedom here.

When you listen to the podcast, I’d be interested in hearing your thoughts.

If your stance is that one set to failure is optimal for inducing neuromuscular adaptations, I’d like to know if you therefore feel that professional bodybuilders, powerlifters, strongmen, and Olympic weightlifters are all “doing it wrong.”

Many PL’ers will run Sheiko, Smolov, Smolov Jr., and/or The Russian squat routine with great success.

I’m a huge fan of HIT training and I’ve written several times about HIT on this blog over the past few years, but I don’t feel that it’s optimal if there are no time constraints. I do believe that it’s the most efficient form of training, however. But I feel that by doing multiple sets, additional hypertrophic and neural adaptations will be stimulated, with the law of diminishing returns applying heavily.

That said, I haven’t scrutinized the research like you, Krieger, and Carpinelli have, and much of my expertise on this topic comes from training myself and others. Therefore, I’d like to know your full position.

You also criticize the fact that I included studies that used different ages and training statuses. These things were controlled for in the statistical analysis; please take the time to understand the statistical analysis before you make such criticisms or make comments such as my paper somehow being “unreliable” or “unscientific.”

James – I apologise for the bluntness of that message, and the comment regarding “unscientific” nature. I think that meta-analyses potentially have a place in science, but I also think caution should be taken by compiling statistics and and attaining a single recommendation.

In your meta-analysis you state that within the criteria “comparison of single to multiple sets per exercise, with all other variables being equivalent”. I disagree that other variables were equivalent between studies, including but not limited to Ostrowski (1997) who couldn’t confirm the number of sets; (3-, 6- and 9-sets [pg148], 1-,2- and 4-sets [pg150] and 3-, 6- and 9-sets [pg151]; Ronnestad, et al., (2007) who I believe added a protein supplement to participants; and Marzolini, et al., (2008) who’s participants were suffering from CAD!

Bret – you mentioned efficiency of training – the enforced 3-minute between set rest time in Ostrowski’s study would have been between 1h12m and 3h36m per workout!! REST TIME! However, this conversation is not about efficiency it’s about science.

There is still so much to learn within this area; Brad is doing a great job of publishing multiple papers on hypertrophy. I think that without genetic knowledge of myostatin and the like on an individual basis this debate will rage on.

I like that intelligent people are engaging in this in such an open forum but at this stage I’m going to clarify that I have said my piece and will cordially step back from this debate to let others have their say.

Thanks, all, and let me clarify that whilst there is disagreement; there is also respect.

1) I believe you have misinterpreted the volume data reported in the Ostrowski et al. paper. The reporting of 3, 6, and 9 sets is the volume *per muscle group*. The table that you refer to reports the volume *per exercise*. I do believe there is a type in the table as the “high volume” is reported as performing 4 sets per exercise, which would be 12 sets per muscle. I’m gathering this was supposed to be 3. Regardless, there is no discrepancy as to overall volume per muscle.

Your comments about the time per workout also is skewed here. Subjects performed 6 exercises per session. Taking 3 minutes rest between sets would equate to 18 minutes of rest for the single set group, 36 minutes for the two set group, and 54 minutes for the 3 set group. If sets lasted, say, 30 seconds per exercise, that would equate to at most a little more than an hour for total training time in the 3 set group.

2) The claim that the Ronnestad et al. study was tained by supplements is a big stretch, IMO. The subjects were given a protein chocolate bar pre-workout and consumed energy drinks (basically sugar and electrolytes). I would hardly call that taking supplements. If anything, it would help to ensure that daily protein needs are met so that hypertrophy can be maximized regardless of the protocol employed. I’d counter that low protein consumption would be a greater issue with confounding results.

3) I would agree that the fact that the subjects in the Marzolini et al. study were CAD patients would be a confounding issue. That said, James did a sensitivity analysis to assess the effects of removing a given study on results; removal of the Marzolini study had no effect on outcome measures.

I’ll conclude by stating that, while I agree with your premise that meta-analyses have limitations that must be understood, they also provide an extremely valuable tool for exercise science. Experiment research in an applied science such as exercise is extremely time consuming. Thus, the sample sizes are invariably small and present issues with statistical power. The ability to pool studies for analysis has huge implications for assessing a given subject, in particular to avoid type II errors privy to single subject analysis.

James K-
In your meta-analysis you state that within the criteria “comparison of single to multiple sets per exercise, with all other variables being equivalent,” as James F mentioned.

Does this mean that all studies used in your meta-analysis used the same repetition speed on strength exercises? In my mind there is a huge difference between a rep that takes 3 seconds and a rep that takes 7 seconds to complete. Just wanted to clarify.

It should be clarified that it is all other variables were equivalent *within the same study*. Thus, repetition speed would be the same between the single and multiple set groups within a particular study. However, repetition speed may have varied between different studies. This was controlled for in the statistical analysis through the use of a random effects model.

I’ll add that Brad already adequately responded to your comment. I will just add something about the presence of CAD in the Marzolini study. The inclusion criteria stated that all variables had to be equivalent between the single and multiple set groups. This is *within each study.* Marzolini met this criteria because both the single and multiple set groups had CAD. Also, unless there is evidence that CAD can somehow impact hypertrophy, there was simply no reason to exclude the study. However, as Brad pointed out, this is also why a sensitivity analysis was performed, just to see if the study was influential on the overall outcomes of my meta analysis, which it wasn’t. So even if I had excluded Marzolini, my results would have been the same.

Bret and Brad-
Although the volume with traditional HIT may not be high enough for optimal muscle hypertrophy (and I agree), how do you feel about the recommended tempo that traditional HIT uses. Most HIT practicioners that I know use around a 2 second concentric, 4 second eccentric, and ease into the transitions (usually adds another second- so a typical rep might take a total of 6-8 seconds. I recently read Brad’s MAX Muscle Plan and I know in some phases of the program he suggested using an “explosive” concentric phase.

Hi Sam, I’m aware of research that supports more explosive training for purposes of maximizing peak muscle activation and tension, and there’s even research that indicates that it’s superior for the purposes of maximizing power production capabilities and muscle hypertrophy too, but I can’t think of the studies by name at this moment. Is slower tempo safer? Sure. Will it offer similar benefits in terms of average tension/EMG and lactate/metabolic stress? I’m sure it would. But I prefer more explosive reps, with the caveat that you don’t shut down muscle activation half-way through the rep because you have to decelerate the bar. You always want to control the rep through a full ROM. Hope that makes sense.

I am a geek that follows both camps. If only the best from both camps could talk in a debate, and not just about studies, but rather practical applications and real world training. Those would be, for me, Brad Schoenfeld, Bret Contreras vs. Drew Baye, James Steele. I’d also throw Skyler Tanner and Keith Norris to the mix, as they are grey area, combination of both.
Both camps actually aren’t really aware of the best programmes of the other camp. Baye, Steele favor, I’d say, around 10 exercises per workout, one set to failure, slow, controlled, but not superslow, 50-90s TUL, no rest in between. So it is much more bodybuilding and each muscle group is worked in 2-3 different sets, not one.
Drew Baye also knows how recovery really works, that it’s not linear, that it’s more about transient disruptions on many levels, he is aware of possible negative outcomes of very high frequency HIT, so he recommends 2-3 times a week.

Both sides are arguing against strawman too often and already approach the studies/debates with desired result in their minds, even the best. Wanna rdicule HIT? Pick a once every three weeks routine of 5 sets. Wanna idicule volume camp? Pick Arnold magazine routine.

Bret, I think you should read Drew Baye’s Project Kratos. It is a bodyweight HIT and will be published soon, I have the preorder version, and I think this book is as good as your Bodyweight Anatomy that I’ve read as well. It is the best HIT book I’ve seen and I have a shelf full of McRobert, McGuff, Fornicola, Brzycki, Mentzer…you get the point:-) The organization and level of consideration put into that book is amazing.

2 How much of a benefit is it to go to failure, as against stopping the set before failure?

3 How important is volume? Is it better to stop before failure and do another set? In this case one would forgo the benefit (great or small) from going to failure, but double the volume. Which is more beneficial?

In these discussions I find that what is missing is the question of going to failure. How much benefit does it provide? Please answer this question, I think it will clarify many questions.

This is in relation to bodybuilders/physique athletes, or anyone looking to increase muscle size; not athletic performance.

I believe it comes down to the ability of the individual to contract the working muscle.

We know that advanced bodybuilder trainees have a far greater ability to contract, whether this be through ‘mind muscle connection’, experience, nervous adaptations, however you wish to explain it.

With that in mind, an advanced trainee would be able to recruit more fibres from 1 set than a beginner. A beginner would likely need multiple sets to maximally recruit fibres (although, they’re still unlikely to get that close to full recruitment), so, I believe, a beginner should focus on increasing volume in order to progress, yet an advanced trainer can/should and will benefit from experimenting with more ‘intensity’ (effort) techniques.

Of course, planning/periodising your hypertrophy training that manipulates all variables, e.g. load, volume, intensity, ‘intensity’ (effort), TUT etc over training blocks/months/whatever will often be superior to just being ‘a volume guy or a HIT guy’. Saying that, once an advanced trainee is experienced enough, they’ll know what works for them and if they have 21 inch arms, who are we to tell him what to do!?

Peak tension would be similar between both styles, but the HVT would have greater TUT.

The HVT would have higher muscle damage, but this wouldn’t be a good thing IMO so the advantage here would go to HIT in my opinion.

But it’s the metabolic stress advantage that can’t be ignored for HVT and hypertrophy, along with the neural coordination benefits for strength.

Again, I’m a huge fan of HIT. I’ve used it myself and with others with great success.

I also feel that there could be very effective ways of utilizing HIT in more unconventional ways to maximize hypertrophy/strength, by employing multiple exercises for the same muscle group but just doing one set.

For example, doing one set to failure of bench press, incline press, military press, decline press, flies, lateral raises, rear delt raises, and rope tricep extensions (8 sets) would do an incredible job of stimulating peak activation/tension in all the fibers of the pec/delt/tri musculature and achieving high levels of metabolic stress without accruing excessive damage. But this protocol is rarely seen and is sort of a blend between HIT and HVT.

If you did a lower body day, an upper body pressing day, and an upper body pulling day, took a day off, then repeated, this would be a highly effective protocol for both hypertrophy and strength IMO.

Bottom line is that protocols should be tailored to the individual’s goals and logistics. The majority of individuals would do best by utilizing HIT as they don’t have a lot of time to train and they need efficiency.

Those more motivated and with more time should periodize, incorporate more volume, and possibly explore with the blended HIT/HVT approach I detailed above.

There are so many fallacies in this article it’s hard to know where to begin. Just for starters:

CLAIM: The majority of published research and an even larger amount of unpublished research shows little or no difference in results between performing one or more sets of an exercise (research showing no difference in the effect of independent variables tends not to be published).
******This is patently false. The meta-analyses by James Krieger (and others) show a clear superiority for multi-set training (and Baye does nothing to substantiate claims that the analyses are flawed). There is no evidence that there is some conspiracy not to publish findings that favor HIT.

CLAIM: …most people without proper instruction will use relatively poor form, moving in a fast and sloppy manner not representative of what is often recommended for high intensity training.
********Another unsupported statement. Research protocols are invariably supervised to make sure proper form is used. He seems to be equating faster movement with “sloppy, poor performance.” This is patently false. Moreover, as fatigue sets in during a set, cadence necessarily slows. The last few reps of a set take a few seconds concentrically.

I don’t have time to go on, but the entire article is a strawman against traditional training. I am not anti-HIT at all. I think it certainly has a place. But those trying to claim that it’s as good as multi-set training for *maximizing* hypertrophic gains are simply not paying attention to the research.

Thanks Brad, I admit it’s hard to evaluate who is correct, I noticed Baye referenced some sources you consider doubtful, like Carpinelli, but then again, this is like a tennis match with a wall instead of a net, many “critiques of critique of critique” and it’s hard to distinguish good one from bad one on without research background. Add “art” and “in the trenches experience” to the mix and it’s impossible.
I also admit, as I am used to slower cadence, about 4/4, sometimes with a 3 second squeeze, that when I see Your or Bret’s training videos it’s great form, but rather fast and especially with fast turnarounds it looks like there is not enough load compared to what I’m used to do.

Absolutely. I agree with your comments. There are myriad facets to maximizing hypertrophy and yes, metabolic stress and methods used to train for this are a huge factor in attaining growth. Yes, volume is a key element to a lifters progress.

I guess, I was just making the point that a rep or a set isn’t exactly the same for everyone….their ability to contract tissue may well make a difference to the outcome (success rate) of the program.

I look at it in a similar way to intense cardio training. We know most clients, when asked to work at 100% intensity, will not work at 100% intensity. Not out of choice, but rather from an inability to have this capacity…plus, they don’t really know what 100% means or what it feels like. (In addition, in terms of duration, I think it’s generally agreed that most untrained individuals may only last 3 seconds at this intensity, compared to 10 seconds for elite athletes). There is a difference between relative or perceived intensity and actual intensity…but that’s beside the point here.

I’ll admit, many factors are involved in this (cardio intensity) and it’s not particularly analogous to my ‘ability to contract muscle’ point, but do you see what I’m getting?!

A simple method that I derived for measuring total intensity is to multiply the intensity of effort by the intensity of load. For example if one has a 1 rep max of 200 lbs. and performs a set with 160 lbs. that’s 80% load intensity. Then if 100% effort with 160 lbs. yields 7 reps, then performing 5 reps would be 71% effort intensity. So multiplying 80% x 71% = 57% total intensity or if you prefer to be more specific, set intensity.

If doing multiple sets with the same load for the same reps, the total intensity would be somewhat higher due to the affects of cumulative fatigue. This can be accounted for subjectively by estimating how many “Reps in the Bank” the person could have done if they continued the set to failure and then dividing the reps completed by the completed reps + bankable reps for the adjusted effort intensity. For example if one did 5 reps and only had 1 left in the bank, that would be 83% (5 divided by 6).

If one wanted a more complete and complicated version of this, one could add in a volume intensity whereby one could arbitrarily select a fixed number of sets as their upper limit. For example if one completes 3 sets and feels that they could have done 5 sets with the same load and same reps, that would be 60% (3 divided by 5) volume intensity. So overall intensity would be 80% x 71% x 60% = 34%.

If one were wearing a heart monitor, a 4th dimension can be added to the formula in terms of either average heart rate for the set or peak heart rate at the completion of the set. One can either use one of many formulae for estimating max heart rate or actual max heart rate. So if ones max HR is 180 and the peak heart rate for the set was 150, that would derive a cardio intensity rating of 83%. So now total systemic intensity would be 80% x 71% x 60% x 83% = 28%.

Yes this 28% figure seems inaccurately low given the level of perceived exertion so one could just add these figures and divide by 4 and have 74% total systemic intensity, which makes more sense to me.

One of the groups trained 3x per week, training 9 exercises for one set each. Despite having trained for several years, the group training 3x week with one set to failure gained an average of 9.7 lbs of muscle and lost 2.3 lbs of fat.

I think those results are outstanding. Each session probably lasted 20-30 minutes.

Just the fact that some respected people still consider 20 minutes twice a week as good as more volume protocols tells us it’s the most efficient workout. It may be suboptimal and bring only 80% of hypertrophy long term, but it feels like you don’t invest time at all and your body composition improves, which includes EPOC, so you basically add HIIT/MRT to the mix.
In real world, eople won’t be that good in really utilising the advantage of 3 sets, they’ll hold back, so the diminishing returns will apply even more. It’ll be more difficult to track progress than with HIT, so they may not achieve progressive overload. Their willpower/decision making capacity for the day may be exhausted, so when the programme isn’t set in stone with only a few exercises, they’ll choose TV instead etc.
And, even if this is not the case:

1 hour/week….80% hypertrophy
4 hours/week….90% hypertrophy

Sure, some will choose the latter, and I have to admit I like the autoregulation philosophy of Matt Perryman that actually is very close to the programming Bret offers in his new bodyweight book…it has it’s advantages to just go with the flow and ditch workout charts, which is possible only with higher volumes and “practice, not performance” mindset. I consider switching to bodyweight protocol 5 times a week to test it. Still, for most HIT seems like the way to go…even if the hypertrophy percentage was more in favour of VT.

That’s a very valid point Ondre. As both a researcher and practitioner, my focus is on optimizing the hypertrophic response to resistance training. It is ultimatley up to the individual to prioritize their goals in this regard. As you note, HIT remains a viable option for those who want a time-efficient muscle-building workout. But there is a clear association between volume and hypertrophy. If maximizing muscle mass is the goal, then a higher volume routine is needed. The amount of volume that maximizes the response remains to be determined (i.e. upper threshold), and will most certainly be different between individuals.

Judging from the quantity and especially the quality of the comments I think the 30m podcast is a great idea, because it is not so east to get 2-3 hrs to listen.

As regards time efficiency, I question the value of the 20 min workout. For a workout you need time to get to the gym and time to get back to work or home. You need time to change and warm up before you exercise. You need time to cool down, probably shower, and to change clothes again. then there is travelling back to work, home whatever. So why not train for 30-50 mins and get a proper workout rather than rushing like a lunatic and risking injury?

If time is a priority I suggest that a proper 45 min workout twice per week is far more time efficient than three stressful 20 min sessions per week.

You rush between exercises, not during exercises. Warm up is generally not utilised when training HIT. I agree that when you go for efficiency, bodyweight or dumbbells at home are better than travelling to a gym.

http://www.renaissanceexercise.com/hvt-a-forum-topic-in-the-inner-circle/
Highly relevant to the topic, natural bodybuilder Joshua Trentine successfully uses HIT as we defined it here, new article from 10th October.
“So…for this contest I use RenEx exclusively. I train 2x/ week and every week….one of the workouts can be as many as 10 exercises, mostly single joint on that day. That workout could take 25…maybe even 30 minutes. The other one is briefer and mostly compound exercises. It is usually done in 20 min. Not so bad so far, but wait….it does mount up as the show draws near.”

Science has its place, but is limited becaues of control variables to make the testing valid. Metanalysis is better, but still only touches on only a handful of factors and variables that equate to far less than the sum required to be anything but generalized information. This falls far short from determining specifically what an individual needs to do to maximize their unique potential.
I have lifted weights for thirty years of my life. I notice that I do gain more muscle mass from higher volume, but I always end up going back to HIT due to overtraining or injury. In fact, the gains that I make from high volume last only a while before I actually begin losing muscle mass, get injured, or feel sick. In the long run, HIT has been much safer and has accumulated more muscle for me due to the forementioned reasons.
So perhaps the race between the turtle and the hare would fit here. Of course long term comparisons between full body workouts (HIT vs High Volume) for different age groups would be hard to compile in scientific testing. Maybe an analysis of optimizing periodization for hypertrophy in different age groups would be more applicable?

Hey Bret, love your podcasts BUT- does this mean no more Strength of Evidence Podcasts?
I cant find the Bret and Brad or B & B connection on iTunes. I can listen via the website, but will you been putting this series on itunes at all in the future?

Great Topic! As James Krieger http://www.weightology.net/ Mentioned In An Above Comment…Tempo…Amongst Many Other Variables Use Of %1 REP MAX./SELECTION & SEQUENCE OF EXERCISES/THEIR INHERENT OVERLAPSE/TIME LAPSE BETWEEN MOVEMENTS/CONCENTRIC & ECCENTRIC MMF/ADEQUATE RECOVERY (just to mention some considerations and certainly not all) play a significant role in applying proper use of the HIT theory. In my experience HIT works like a charm when dialed in…but should likely be periodized in a macrocycle. Currently using HIT as our ‘deloading’ phase in a Wendler like 5-3-1 program. Keep Crushin’ This Shit! You guys hit great topics…Thank you! Peace-Matt

Awesome, I read above that HIT has no place with athletic development. What about coaches like Micky Marotti or Ken Mannie? They’re HIT guys who develop beasts. Also look into what Dr. Ken Leistner has done with athletes and HIT. Law of specificity applies. Want to get better at a sport? Practice that sport.